Cutting-tool



H. K. PORTER. CUT'HNG TOOL. APPLICAHQH man Dc.20.19|s.

1,348,735. Patented Aug. 3,1920.

7A 5 @m 1 z I w s HENRY K. PORTER, OF BROOKLINE, MASSACHUSETTS.

CUTTING-TOOL.

Specification of Letters Patent.

Patented Aug. 3, 1920.

Application filed December 20, 1918. Serial lilo. 267,579.

To all whom it ma concern:

Be it known tiat I, HENRY K. PORTER, a citizen of the United States, residing at Brookline, in the county of Norfolk and State of Massachusetts, have invented new and useful Improvements in Cutting-Tools, of which the following is a specification- This invention relates to cutting tools adapted to be operated by hand, and is more particularly adapted to tools for cutting metal rods and bars.

The object of the invention is to provide a cutting tool for the purpose specified which may be operated with a smaller expenditure of strength by the person using the tool and giving a much increased power at the cutting edges of the tool.

The cutting tool of this invention is of that class in which a pair of cutting jaws are operated by means of a pair of handle levers and in certain details relating to the adjustment of the handle levers is substantially the same as the construction for the same purpose set forth in my Patent No. 484,670, patented October 18, 1892. In tools of this character, it has been customary, in order to secure increased leverage and, therefore, apply increased power to the out ting jaws of the tool, to make the handle levers of as great length as possible. When the handle levers are made of excessive length, for example so that when the levers are spread apart they are separated at their extreme ends by a distance of thirty-six inches, which is extreme in tools of this characten then the hands of the user of the tool must be spread far apart in order to grasp the ends of the handles, in which case it is customary, in order to obtain power to close the handles, to grasp the handles and then throw the body back.

It is a well known fact that when the hands are spread far apart and then brought toward each other, the power which can be applied by a man using the tool is very much reduced as compared with the power which the same man can exercise when the handles are spread apart about one-half the distance, for in that case the user of the tool can operate the handles in an entirely different manner, viz, he can place one handle against his chest and move the other handle by pulling in a direction substantially longitudinally of his arm instead of laterally thereof.

It is the object of this invention to produce a combination of mechanisms whereby a comparatively short pair of handles may be utilized to impart great power to the cutting jaws, so that the objection hereinbefore recited may be overcome by reason of the fact that although the handles are approximately only eighteen inches long, the power which can be obtained will be greater than could be obtained with the ordinary cutting tool with handles thirty in; hes long.

The invention consists in the combination of mechanisms whereby the cutting instru mentalities are operated and in the specific formation or shape of the cutting edge or edges of the two cooperating parts constituting the cutting instrumcntalitics of the too The invention further consists in the combination and arrangement of parts set forth in the following specification and particularly pointed out in the claims.

Referring to the drawings:

Figure 1 is a plan view of my improved cutting tool.

Fig. 2 is a plan partly in section of a portion of the same.

Fig. is a sectional elevation taken on line 3-3 of Fig. 1.

Fig. 4 is a sectional elevation taken on line 4-4 of Fig 1.

Figs. 5, 6,. 7 and 8 are detail cross sections of a bar illustrating the cutting operations of the tool.

Like numerals refer to like parts throughout the several views of the drawings.

In the drawings, 10, 11 are cutter levers pivoted at 12 and 13, respectively, to straps 14. Each of these cutter levers hasa cutting edge, one portion 15 extending at an angle to another portion 16 thereof, the two portions 16 contacting with each other and being parallel to each other when the jaws of the cutters are closed, as in Fig. 1, while the portions 15 of the edges of said cutters diverge from each other, both when the cutters are closed and when they are open.

The cutter levers 10 and 11 are rovided with teeth 17 and 18 which mesh into each other and thus cooperate in the opening and closing movement of the cutter levers.

A pair of handle levers 19 and 20 are pivoted together at 21 and are provided with stops 22 and 23 adapted to abut against each other to limit the distance to which the handle levers 19 and 20 can be ap+ preached toward each other.

The handle levers 19 and 20 have adjusting levers 2% and 25 pivoted thereto at 26 and 27, and each of these handle adjusting levers forms, in ell'ect, a. part of the handle levers. Said adjusting levers are each provided with an adjusting screw 28 having scrcw-threaded engagen'ient therewith and adapted to hear at its inner end against its respective handle lever. Each of said haudle. levers has an eye-bolt :59 pivoted thereto at 30 and each of said eye-bolts has a looking nut 31 in screw-threaded engagement therewil h and adapted to bear against the outer edge of its respective adjusting lever 24 or 25.

The adjusting levers 24- and are pivoted at 32 and 33 respectively, to one end of each of a pair of levers 34 and 35, which levers are located intermediate the cutter levers l and ll and the handle levers l9 and 2 and crossing each other are pivoted together at 36. The opposite. ends of the levers 34 and 35 from those ends to which the adjusting levers are pivotally secured. are pivotally attached at 37 and 38 to the levers l1 and ll), respectively.

It will be seen that to adjust the pivots 32 and 33 away from each other the nuts 31 on the eye-bolts 29 must be first loosened. The adjusting screws 28 will then be screwed inwardly and will thus force the adjusting levers 24 and 95 apart at the ends thereof which are pivoted to the levers 34 and 35. When the desired amount of adjustment is thus obtained, the adjusting levers are locked in position relatively to their respective handle levers by tightening up the lock nuts 31 on the eye-bolts 29. This adjustment takes up all wear at the different points where the levers are pivoted to each other and also compensates for any wear or grinding ofl of the cutting edges of the cutter levers.

It will be understood that the adjusting levers on the handle levers are not new per so, as substantially the same construction is described and illustrated in my said patent, but the combination of this particular form of adjustable handle lever with the other instrumentalities of this invention assists in the production of new and useful results as compared with the form of my in vention illustrated and described in said patent. It is evident that the adjusting levers form, in effect, a part of the handle levers, and if adjustment of the handle vers is not required then the adjusting devices of said adjusting levers as such could be omitted and the same made an integral part of the handle levers 19 and 20.

The operation of the device is as follows: A piece of a metal rod 39 is placed between the diver in portions 15 of the cutting edges of t e ivers 1-0 and 11 near the outer ends of said levers and the handle levers 19 and 20 are then brought toward each other to the position illustrated in Fig. '1, thus bringing the ruttingedges 15 toward each other and cutting the metal liar partly through, as illustrated in Fig. "lhe hanolle levers are then moved apart and the cutting edges 15 are thus also moved apart and the bar 3!) is then moved inwardly between the cutting edges 15 and toward. the portions 16 of said cutting edges. The handle levers are then brought toward each other against and the cutters are moved toward each other to cut the bar 39 on the same line as before, as illustrated in Fig. 6. This operation is repeated and the next cut leaves the bar in the condition illustrated in Fig. T, and finally the cut portion of the bar is moved in between the cutting edges l6, l6 and a motion of the lovers to ward each other completes the cutting operation by entirely severing one portion ot the bar from the other.

It will be seen that each cut oi the bar is :omj'mratively slight in extent, but that great power is obtained by the arrangement oi the different levers and by the leverage thus obtained, and furthermore the leverage at the operative portion of the cutting edges of the cutter levers is increased each time that the bar is moved nearer to the pivots 12 and 13 of said cutters.

It will be seen that even when the handle levers l9 and 20 are brought together as near as poi-1sible, the center of the pivot 21 is out of alim-ment with the pivots 32 and 3 and that a toggle action is thus secured between the two handle levers l9 and 20 which is transmitted to the intermediate levers Ill and 35, thus obtaining great power.

Furthermore, it will be noted that the distance from the pivots 32 and 33 to the cen tral pivot 36 of the levers 34 and 35 is several times that of the distance from said pivot 36 to the pivots 37 and 38, thus obtaining another increase in leverage, and, furthermore, that the distance from the pivots 37 and to the pivots 12 and 13 of the cutter levers is greater than the distance from the pivots 12 and 13 to the point on the cutting edges where the cutting takes place, thus securing another leverage and the distance from the outer ends of the handle levers 19 and 20 to their common pivot 21 is many times greater than the distan e from said common pivot 21 to the pivots 32 and 33 where the adjusting levers, forming a part of the handle levers, are connected to the intermediate levers 34 and 35. Therefore, the leverage from the outer ends of the handle levers 19 and 20 to the cutter levers 10 and 11 is multiplied many times, resulting in great power of cut as compared with the power applied by the user to the handle levers and enabling the use of a comparatively short pair of handle levers to secure great cutting power and the more efiicient utilization of the man power by which the cutting tool is operated.

It will be understood that the manner of I utting oli' a bolt or bar by successive steps, hereinbeiore described, is applicable to bars and bolts of comparatively large diameter, but where it is desired to sever a thin piece oi metal or a piece of metal of small diameter, then such a piece can be inserted between the portions 16 of the cutting edges of the cutter levers and severed at one operation of the handles of the instrument.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A cutting tool having, in combination, a pair of cutter levers, a pair of handle levers pivotally connected to each other and an adjustable member on each of said handle levers and forming, in effect, a part thereof, means to adjust said members toward and away from each other and a pair of levers pivotally connected together and crossing each other intermediate said cutter and handle levers, the opposite ends of said intermediate levers being pivotally connected to said cutter levers and to said adjustable members, respectively.

2. A cutting tool having, in combination, a pair of cutter levers, a pair of handle levers, pivotally connected to each other, an adjusting lever pivoted to each'of said handles and forming, in effect, a part thereof, an adjusting screw on each of said adjusting levers having screw-threaded engagement therewith and adapted to bear against its respective handle lever, means whereby said adjusting levers may be moved away from each other and a pair of levers pivotally connected together and crossing each other intermediate said cutter and handle levers, the opposite ends of said intermediate levers being pivotally connected to said cutter levers and to said adjusting levers, respectively.

3. A cutting tool having, in combination, a pair of cutter levers, a pair of handle levers pivotally connected to each other, an adjusting lever pivoted to each of said handles and forming, in effect, a part thereof, an adjusting screw on each of said adjusting levers having screw-threaded engagement therewith and adapted to bear against its respective handle lever, an eye-bolt pivotally mounted on each of said handle levers, a nut on said eye-bolt adapted to bear against its respective adjusting lever to lock it in position, whereby said adjusting levers may be adjusted toward and away from each other and a pair of levers pivotally connected together and crossing each other intermediate said cutter and handle levers, the opposite ends of said intermediate levers being pivotally connected to said cutter levers and said adjusting levers, respectively.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

HENRY K. PORTER. Witnesses:

CHARLES S. Goonmo, FRANKLIN E. Low. 

